Here are my recomendations:
Phan Chao Tom (shrimp paste on sugar cane)
Phan Chia Gio (fried egg rolls)
Goi Cuon (rice paper roll with pork and shrimp)
Bahn Tam Bi (shredded pork, coconut milk, w/ large rice noodle)
Bun Bo Nuong (grilled beef with rice vermicelli )
Com Bi Cha Thit Nuong (grilled pork, shredded pork, and baked egg with rice)
Soda Chanh (lemonade soda)
Obviously, you have to get some pho, though i don't think their version stands out over ones elsewhere (still very good, though).
The two dishes i think they do by far better than anyone else are the fried egg rolls (which you wrap in lettuce and herbs before dipping into sauce) and their "broken rice" dishes (probably just listed as rice dishes in the back). in particular, i'd recommend the rice dish with pork chop, shredded pork and "baked egg," which is some delicious frittata-like cube of egg, mushrooms and a little meat.
i also like another dish which ethey might call mini-vermicelli or something like that. noodle-patties with bbq'd meats, again wrapped in lettuce and dipped into sauce.
i'd avoid their curry (watery and flavorless).